Dressing-hammer.



c. KERN.

DRESSING HAMMER.

APPLICATION FILED 3.16. 19|5.

l ,2 1 2,502 Patented Jan. 16, 1917.

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Snecicati'itof Letters Patent.

Paternal Jarlt, ,19.17-

Application led February 16, 1915. Serial No. 8,664.

To all whom t may concern:

Be it known that I, CONRAD KERN, a citizen of the Republic of fSwitzerlanfhresiding atZurich, Switzerland, have invented new and useful Improvements in Dressing- Hammers; and ,I d o hereby declarethe ,fol lowing to be a full, clear, 'and exact description of the invention, such' as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this SP sififnton nown stone dressin hammers, having interchangeable cuttinaads, have a Cavity formed in the harllrrvler.l body to receive a pin Qrtsnon 'formed 0'1'1 thefcuttinghead- .1t has bnellndrhgwever; that it is not advisable tQPrQvde. the beadrere with Such fr tenon, `14S-the lite ,of the head ieee is Very Short, rpitharts .cest Qf manufacture should be as rmallis'rosibie. 1f. are had piep@ and a@ @non -QWH 01.1.@ Die@ the-ma0hn1ngj9fthe tenon increases, however, the cost of the whole piece to such an amount that it is quite ,impor 1.1.@ tomanulfaturq Such head QCQS 0h aller-.ge tleiFQr this reason 1t is been premised4 t0 manufacture the, tenons Separately t0 Press. them afterward 111m the head pie e. This proceeding has however, the drawback that the tenonisgnot eis. .inserted exactly@ vertical Posltlor irri.; the'lleidrse, .in .which @are the latter ribes not rit Asupply 0,11 the .hammerhedy alien it S...Sru there@ Thisrendqrs the iafiflins, ft #histamine mech. mereinsult and 1t in uences in a de'trimntahld manner eq ali Otthlworka wir@ Grever, lsgd. niece, 1,968.11@ Prvpgirly on grimper ,bedr it, is milch mere, ,hable t0 il .herresent `relrtivn..s fvrrrirs .in providirlgffthe f @website @were ,heed ,with .a srity .wrist vampire. a -pw or anon resi integr 1 With-a hammer: wir fOr estirpare@ swarming. the above named ,@,trens- .The .Cavity and tenen. @raide- 'gnedfo .Permit verrader movement vof i @inserire the cutting head on .theLbq y Wre trthpn the @figs ott e e,. s

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Arce! are@ erasererased head` pieces may be fixed without further ado to the hammer body and in order to secure a good fitting of the head piece on the tenon and a proper working with the hammer. To prevent the pin which presses the slotted hammer body outward from projecting too much beyond the side Vfaces of the' hammer body, 'in which'cas'e it would be in the way 'of the workmanv and prevent a 'proper handling of the hammer, it is n'eces sary that said tapering pinV is always driven exactly the same 'amount' into' the hammer body, when a new head piece is'Xed tosaid body. Further, it hasbeen found that the head piece can be fixed in a particularly secure manner to the hammer body if the tenon of the hammer and the cavity of the head piece have atapering shape of such a form that the head piece 1s prevented from moving 'away from the adjacent surface of the hammer body. A further advantage which may be attained by giving to the tenon and the cavity adapted to receive the latter 'a tapering shape consists in that the slotted tenon exerts the pressure efectin the connection between the, head piece an the hammer, `body near its root uponsaid head piece when the fastening pinl is inserted into'the hole provided for 1t 1n the hammer. Owing to thls arrangement a much better fitting of the head piece on said tenon is obtained and the quality of the work is very much increased, since Such'a tapering tenonhas a very small elasticity. Atap'ering tenon acting in the hereinbefore described manner upon the' surrounding parts of the head piece is also less liable to break when the hammer is handled 'in `an inappropriate manner.

'Several forms of carrying the invention into effect 'are shown by' way of example in the accompanying drawings in which:

AFigure -1 vis a perspective view or a first construction, Fig. 2 is afront View on 'an enlarged scale of the hammer body and the head piece fixed thereto of the hammer shown in Fig. 1. Fig. 3 is a side view, partly in section of the hammer parts shown in Fig. 2; Fig. 4 shows on the scale of Figs. 2 and 3 a front view of a second embodyment of my invention; Fig. 5 is a side view partly in section of the parts illustrated in Fig. 4; Fig. 6 shows on the scale of Figs. 2 and 3 a front view of a third embodiment of my invention; Fig. 7 is a longitudinal section of the hammer parts illustrated in Fig. 6; Fig. 8 is a longitudinal section on a' still larger scale through a part of the hammer body and the head piece before the insertion of the tapering fastening pin; Fig. 9 is a corresponding view of these parts after the insertion of the fastening pin.

Similar numbers refer to similar parts throughout the several views.

1 denotes the hammer body. The front surface 2 of this body, to which is fixed the head piece provided with a cutting face, has a slightly tapering tenon 3. The hammer body 1 has a longitudinal slot 4 passing also through the middle of the tenon 3. According to the embodiment of the invention shown in Figs. 2 `and 3 the slot 4 is provided near the front surface 2 with concave surfaces 5 forming part of a slightly tapering bore 5.

6 denotes the head piece provided with a cutting face 7 The head piece has a cavity 8 adapted to receive the tenon 3.

9 denotes a tapering fastening pin, which may be inserted into the bore 5.

18 denotes the eye adapted to receive the handle 19.

For the purpose of fixing the head piece 6 to the hammer body 1 shown in Figs. 2 and 3 said piece 6 is pushed in such a manner upon the tenon 3 that the end surface of the head piece 6 lying opposite the cutting surface of this piece touches the front surface 2 of the hammer body 1. The pin 9 is hereupon inserted into the bore 5', so that the slotted tenon 3 is pressed outward and against the Walls of the cavity 8. (Fig. 9).

According to the embodiment shown in Figs. 4 and 5 the pin 9 is replaced by a screw 10, which is screwed into the hammer body 1 to press a part of the latter lying on one i side of the slot 4 and the tenon 3 outward.

According to the embodiment of the invention shown in Figs. 6 and T there is fixed to each end surface of the hammer body 1 a head piece 6 having a cutting surface. The attachment of the head' piece 6, which has to be fixed to the right hand end of the body7 1, is effected in the same manner as in the embodiment shown in Figs. 3-4, `with the difference that the borev 5 is drilied into the tenon 3, so that the tapering pin 9 passes also through this head piece. For the purpose of fastening the other head piece to the cavity:A

left hand end of the hammer body 1 there is provided on this end a tenon 3 having an annular groove 10. The head piece 6, which has to be pushed on the tenon 3 has a slightly tapering bore 11 disposed in such a manner that a tapering pin 9 passing through this bore touches at one point the Wall of the annular groove 10 so that this head piece is fixed to the hammer body as soon as said pin is driven tightly into the bore 11.

Owing to the fact that the tenon 3 is provided in the hereinbefore described embodiment of the invention on the hammer body 1, it is possible to machine this tenon. The proper taper is given the teno-n in machining which increases only slightly the price of the whole hammer, since the more expensive hammer body may be used for a very long time and only the cheaper head piece has to be scrapped after a short use. Moreover, the machining of the tenon 3 secures a snug fit of the head piece on the hammer body.

As may be seen in Fig. 9 the head piece 6 provided with a tapering cavity, which is fixed to the tenon 3, is prevented from moving away from the supporting face 2 of the hammer body l and the tenon exerts its pressure near its root upon the head piece 6. As I have shown at the beginnin of the specification these are features, w ich are essential for obtaining good results with such a hammer.

What I wish to claim is:

1. A dressing hammer comprisin a hammer body having a tenon formed t ereon, a detachable head having a cutting face on one side, and a cavity in the opposite side to receive the tenon and adapted to permit angular movement of the head, said cavity being of greater depth than the length of the tenon whereby said opposite side of the head engages the hammer body, and means to move the tenon into en a ement with the 11G sides of the cavity to loc t e head onto the body.

2. A dressing hammer comprising a body portion having an integral tenon and a central longitudinal slot extending through the tenon, a detachable head having a cutting face on one side, and a cavity in the op osite side to receive the tenon and adaptedp to permit angular movement of the head, said being of greater depth than the lengt of the tenon whereby said opposite side of the head en a the hammer body, and means to sprea t e tenon to engage the sides of the cavity and lock the head onto the body.

3. A dressing hammer comprising a body portion having an integral tenon and a central longitudinal slot extending through the tenon, a detachable head havin a cutting face on one side, and a cavity in e opposite 130 side having inwardly diverging Walls and adapted to receive the tenen, said cavity being of greater depth than the length of the tenon whereby sald opposite side of the head engages the hammer body, and means to force the tenon against said diverging walls to lock the head onto the body.

4. A dressing hammer comprising a body portion having an integral tenon and a central longitudinal slot extending through the tenon, a detachable head having a cutting face on one side, and a cavity in the opposite side having inwardly diverging Walls and adapted to receive the tenon, said cavity being of greater depth than the length of the tenon, whereby said opposite side of the head engages the hammer body, and a tapering pin passing transversely through the tenon and head.

5. A dressing hammer comprising a body portion having an integral longitudinally slotted tenon extending beyond the end of the body, a detachable head having a cutting face on one side and a cavity in the opposite side to receive the tenon and adapted to permit angular movement of the head, the outer diameter of the cavity being greater than the normal diameter of the tenon, the walls of the cavity diverging inward and of a greater length than that of the tenon, and means to force the tenen into engagement with the Walls of the cavity, whereby the opposing faces of the head and body are held in contact.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

CONRAD KERN. Witnesses:

ERNST FISCHER, CARL GUBLER.

Uopies o! this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

